EarthQuakeUpdater/app/src/main/java/com/example/earthquakeupdater/EarthquakeActivity.java
<reponame>nishtha2405/HackFest<filename>EarthQuakeUpdater/app/src/main/java/com/example/earthquakeupdater/EarthquakeActivity.javapackage com.example.earthquakeupdater;

import android.app.LoaderManager;
import android.app.LoaderManager.LoaderCallbacks;
import android.content.Context;
import android.content.Intent;
import android.content.Loader;
import android.net.ConnectivityManager;
import android.net.NetworkInfo;
import android.net.Uri;
import android.os.Bundle;
import android.view.View;
import android.widget.AdapterView;
import android.widget.ListView;
import android.widget.TextView;

import androidx.appcompat.app.AppCompatActivity;

import java.util.ArrayList;
import java.util.List;

public class EarthquakeActivity extends AppCompatActivity
        implements LoaderCallbacks<List<EarthQuake>> {

    private static final String LOG_TAG = EarthquakeActivity.class.getName();

    // URL for earthquake data from the USGS dataset
    private static final String USGS_REQUEST_URL =
            "https://earthquake.usgs.gov/fdsnws/event/1/query?format=geojson&orderby=time&&limit=40";

    /**
     * Constant value for the earthquake loader ID. We can choose any integer.
     * This really only comes into play if you're using multiple loaders.
     */
    private static final int EARTHQUAKE_LOADER_ID = 1;


    private EarthquakeAdapter mAdapter;


    private TextView mEmptyStateTextView;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        ListView earthquakeListView = (ListView) findViewById(R.id.list);

        mEmptyStateTextView = (TextView) findViewById(R.id.empty_view);
        earthquakeListView.setEmptyView(mEmptyStateTextView);

        // Create a new adapter that takes an empty list of earthquakes as input
        mAdapter = new EarthquakeAdapter(this, new ArrayList<EarthQuake>());

        // Set the adapter on the ListView so the list can be populated in the user interface
        earthquakeListView.setAdapter(mAdapter);

        earthquakeListView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
            @Override
            public void onItemClick(AdapterView<?> adapterView, View view, int position, long l) {
                // Find the current earthquake that was clicked on
                EarthQuake currentEarthquake = mAdapter.getItem(position);

                // Convert the String URL into a URI object (to pass into the Intent constructor)
                Uri earthquakeUri = Uri.parse(currentEarthquake.getUrl());

                // Create a new intent to view the earthquake URI
                Intent websiteIntent = new Intent(Intent.ACTION_VIEW, earthquakeUri);

                // Send the intent to launch a new activity
                startActivity(websiteIntent);
            }
        });

        // Get a reference to the ConnectivityManager to check state of network connectivity
        ConnectivityManager connMgr = (ConnectivityManager)
                getSystemService(Context.CONNECTIVITY_SERVICE);

        // Get details on the currently active default data network
        NetworkInfo networkInfo = connMgr.getActiveNetworkInfo();

        // If there is a network connection, fetch data
        if (networkInfo != null && networkInfo.isConnected()) {
            // Get a reference to the LoaderManager, in order to interact with loaders.
            LoaderManager loaderManager = getLoaderManager();

            // Initialize the loader. Pass in the int ID constant defined above and pass in null for
            // the bundle. Pass in this activity for the LoaderCallbacks parameter (which is valid
            // because this activity implements the LoaderCallbacks interface).
            loaderManager.initLoader(EARTHQUAKE_LOADER_ID, null, this);
        } else {
            // Otherwise, display error
            // First, hide loading indicator so error message will be visible
            View loadingIndicator = findViewById(R.id.loading_indicator);
            loadingIndicator.setVisibility(View.GONE);

            // Update empty state with no connection error message
            mEmptyStateTextView.setText(R.string.no_internet_connection);
        }
    }

    @Override
    public Loader<List<EarthQuake>> onCreateLoader(int i, Bundle bundle) {
        // Create a new loader for the given URL
        return new EarthquakeLoader(this, USGS_REQUEST_URL);
    }

    @Override
    public void onLoadFinished(Loader<List<EarthQuake>> loader, List<EarthQuake> earthquakes) {
        // Hide loading indicator because the data has been loaded
        View loadingIndicator = findViewById(R.id.loading_indicator);
        loadingIndicator.setVisibility(View.GONE);

        // Set empty state text to display "No earthquakes found."
        mEmptyStateTextView.setText(R.string.no_earthquakes);

        // Clear the adapter of previous earthquake data
        //mAdapter.clear();

        // If there is a valid list of {@link Earthquake}s, then add them to the adapter's
        // data set. This will trigger the ListView to update.
        if (earthquakes != null && !earthquakes.isEmpty()) {
            //mAdapter.addAll(earthquakes);
            mAdapter.addAll(earthquakes);
        }
    }
    @Override
    public void onLoaderReset(Loader<List<EarthQuake>> loader) {
        // Loader reset, so we can clear out our existing data.
        mAdapter.clear();
    }
}